Definition

Gastrointestinal stromal tumors (GISTs) are a type of tumor that occurs in the digestive system. The digestive system includes the esophagus, liver, stomach, gall bladder, large and small intestines, and rectum. The digestive system processes food to fuel the body and gets rid of waste. About half of GISTs occur in the stomach, but they can occur anywhere in the digestive system.

GISTs are rare. All GISTs are now considered potentially cancerous.

Digestive System

Causes

The cause of GISTs is not well understood.

Many people with GIST have a defect in a gene called c-kit. Usually, this gene is not active. However, in people with GIST, the c-kit gene often has a defect and is active, which enables the cells to grow and divide uncontrollably. This may explain why a GIST forms.

Theories about GISTs say that they begin in special cells of the digestive system. These cells are called interstitial cells of Cajal (ICCs). They send signals that tell the digestive system to contract, which moves food and liquid through the digestive system.

Risk Factors

GIST is most common in people over age 50. It is rare in children. Risk factors for GIST are mostly unknown. Possible risk factors include:

Treatment

Talk with your doctor about the best treatment plan for you. Treatment options include:

Surgery

Surgery is used to treat a GIST that has not spread. Surgery to treat GIST should be done by an experienced cancer surgeon. GISTs are delicate tumors. There may be an increased risk of cancer spreading if the sac surrounding the GIST is opened during surgery.

You may be given medications to shrink the tumor before surgery. For small tumors, laparoscopic surgery may be used.

Even if the tumor is large or growing into other organs, your doctor may use surgery to remove some or the entire tumor. This reduces the chance that the tumor will grow large enough to block the digestive system.

Medication

You may be given a medication called a tyrosine kinase inhibitor. It may make the tumor shrink or stop growing.

Huang HY, Li CF, et al. A modification of NIH consensus criteria to better distinguish the highly lethal subset of primary localized gastrointestinal stromal tumors: a subdivision of the original high-risk group on the basis of outcome.
Surgery. 2007;141(6):748

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.